The broad objectives of this 3 year qualitative sociological study are: to identify and describe the sociological processes and dynamics of informed consent and human subject research in public and privately funded AIDS clinical trial research; and to analyze and compare how the organization and social context of AIDS research affects the approaches, interpretations, and decision-making practices of health professionals and patients. The study has five specific aims: 1) to explicate the role and actions of referring physicians with regards to patient participation on clinical trials; 2) to specify the factors that impact the decisions of patients to seek out, consent to, participate in, and withdraw from clinical trials; 3) to discover how, and the extent to which the actions taken and decisions made by physician-investigators to recruit, inform, elicit consent, and oversee patients on clinical trials are influenced by the organization of clinical research; 4) to investigate how, and the extent to which, the role, relations, and decisions of research nurse coordinators are shaped by the organization of clinical research; 5) to intervene by developing a "social process" model of informed consent decision-making in AIDS that has applied and theoretical implications for other domains of health care and for medical and nursing practice. Three types of ethnographic coding techniques will be used to analyze data gathered through participant-observation, semi-structured interviews, and review of printed materials: 1) triangulation, in order to cross check personal claims and accounts with documentary evidence and behavior recorded in the field; 2) cross-case and cross-site comparison, to compare how social processes emerge and transform within specific cases and organized settings; and 3) frequencies of response, to detail the occurrence of themes, concepts, and categories of analysis. The interpretative goal of the study is to construct empirically-driven narrative accounts of the social processes and dynamics of informing, consenting, and participating on AIDS clinical trials, and to explicate factors that impede the exercise of informed consent decisions by physicians, nurses, and patients so that new "process" models can be developed and tested in AIDS and other research settings.